Thrust reversing device for jet engines



Nov. 4, 1958 s. P. COMPTON ET AL 2,858,669

THRUST REVERSING DEVICE FOR JET ENGINES Filed Sept. 15, 1953 2Sheets-Sheet i INVENTORS. STANLEY P. COMPTON FRED W. MUSTERER MalenaNov. 4, 1958 s. P. COMPTON ET AL Tf-IRUST REVERSING DEVICE FOR JETENGINES 2 Sheets-Shee Filed Sept. 15. 1955 INVENTORS. .STANLEY P.COMPTON FRED w. MUSTERER 161m Br K3210;

GIN?! FOR APPL CINTS 2,858,669 THRus-T REVERSiNG DEVIC FOR'JET StanleyP. C0m'ptoi1,. San Diegogiand Mnsterer,

Solana Beach, N Califi, assignors to- The Ryan Aero- 1 nautical Co., SanDiego, Ca'lifl, acorporationdf fornia m .Y nppi'ication'september 15,1953; S erial N '4 Claims. cred-#351514) if;

The present invention relates generally to jetengines and moreparticularlyto a thrust reversing device for jet engines. h i I:

The primary object of this invention is toprovidea means for temporarilyreversing the thrust ofa jet engine to obtain a braking effect on anaircraft when landing in confined areas.

Another object of this invention is to pr ovidcia thrujst reversingdevice which is contained .within the jet engine and which doesnotinterfere with the normal operation ofthe engine.

Another object of this invention. is'to provide jet engines and aircraftwith a minimum of structural modification.

, Finally, it is an object to. provide a thrust reversing device of theaforementioned .character which is simple, safe and convenient tooperate, anclwhich will, give generally efficient and durable service.

With'these and other objects definitely in view, this invention consistsin the novel construction, combination and arrangement of elementsandportions as will be hereinafter fully described in the specification,particularly pointed out in the claims andillustrated in thedrawingwhich forms a material part of this disclosure and-where- .in similarcharacters of reference indicate similar or identical elements andportions throughout the specification and throughout the views of the,drawing, and in tion view' rear fuselage showing the relative" oc'ationsof the' 'exhaust diverter components.

Fig. 3 is a sectional view taken on the line 33 of Fig. 2.

Fig. 4 is a sectional view similar to Fig. 3 but showing the exhaustdiverter in the normal thrust position.

Fig. 5 is a sectional view taken on the line 55 of Fig. 2.

Referring now to the drawings, the device is attached to a jet enginegenerally designated by the numeral 10, the engine being installed inthe rear fuselage 12 of a conventional jet aircraft. Within the tailpipe 14 of the jet engine 10 is an axially movable diverter cone 16which, in the forward and operative position, seats against the innercone 18 of the jet engine immediately aft of the turbine 20.

, 2,858,669 Patented Nov.- 4, 1958 The. pipe 14 includes an outer cone22, tapering from the full diameter of the turbinfe 20 to the smallerdiameter of; the tailpipeextension 24. Atthe junction outer cone, 22:.and the extension 24, said outer cone is provided with a. pair ofopposed openings 26.

The fuselage shell isalsoprovided with a pair of openings S D, whichareeach covered by a pair *of hinged doors gland. are generallyinalignment with the openings 26.

Between the. openings '50 and 26 'at each side of'the [fuselage area-plurality of; deflector vanes 34, 36, 38 and .40respectively, fronrfront to rear.

The airframe structure illustrated in the drawings is .typicalLofconventional jet aircraft and need" not be described in detail herein.

.- 'lhe diverter-cone 16 comprises'a frusto-conical throat portion 42from which extends a tail portion 44.-' The throat portion-"42 istapered to fit substantially flush against the inne-rf surfac'e of theouter come 22, while the tail-portiou 44 is; a smooth sliding 'fi'twithinthe tail pipe extension 24. The diverter cone 16 is moved axiallyin;the';tail-, pipe 14 by any suitable means illustrated here- ;in'asiiuidractuated'jacks '46 which are mounted on the ,outs'ide'of theextension 24 on suitable brackets'48-and 50., :The push rods 52extending from the jacks 46, pass throughthevanes 36, 38 and 40'by wayof suitable apertures 54, and are attached to brackets 56 on the throatportion--42. Since in many typesof jet'engines, the inner crime 18 issupported by a plurality of radial struts58, v

the throat portion-42 is illustrated as having slots 60 to 'fit;aroundsaid struts when in the forward position as shown in Figs. 1 and 3."*"Fheupper and lower ends of the vanes 34 to '40: are enclosed-by coverplates 62to provide ducts through the fuselage shell 28 to the outsideof the aircraft. The vanes 34 to 40 are shaped to divert the flow ofexhaust" gases from a normally rearward direction and to ejectthe gasesgenerally forwardly from the openings '30. The actual shape ofthe"vanes34 to '40 may be determined aerodynamically to suit the partcular' flowcharacteristics of the jet 'ngin'e exhaust.

-The' doors 32 are mounted onhinge rods '64 at the upper and lower edgesof the openings 31), said doors 'openi-ngoutwardly from the fuselage asshown-in Fig.

5. The doors are opened and closed by mean'scf fluid actuated jacks 66which are connected to levers 68 attached to the hinge'rods 64. Thejacks 66 are mounted on a suitable brackets 70 secured to the fuselageshell. The jacks 66 are operatively interconnected to the jacks ,46 sothat the doors 32 open as the diverter cone 16 moves wellfunderstood bythose skilled in the art. g 3 'Witli' thethru'st reversing device in itsnon-operative position as shown in Fig. 4, the diverter cone 16 is atits aft position in close contact with the tail pipe 14, and the doors32 are closed. Thus the openings 26 are sealed oif and the exhaust gasesfrom the jet engine are permitted to follow their normal path throughthe tail pipe 14, .as shown by the arrows, and emerge from the outlet 72as a propulsive thrust.

When a reverse thrust is required to decelerate the aircraft, as whenlanding in a restricted space, the diverter cone 16 is moved forwardlyso that the forward edge 74 of the throat portion 42 seats firmlyagainst the inner cone 1 8. At the same time, the doors 32 are opened.The exhaust gases are now restricted to the annulus between the throatportion 42 and the outer cone 22, and are prevented from entering thetail pipe extension 24 thrust.

3 by the tail portion 44 of the diverter cone, which is still engagedtherewith as shown in Fig. 3. The only escape for the exhaust gases isthrough the openings 26 and between the vanes 34 to 40 as shown bythearrows. The exhaust gases emerge from the openings 30in a forwardlydirection and so provide the necessary braking or reverse This reversethrust is also useful in" combat maneuvers, the sudden decelerationallowing the aircraft to turn more sharply with obvious advantage. '1

During the present landing procedure of jet aircraft, it is customaryfor the engine to be kept running at 50% thrust or higher due to therelatively slow acceleration-of a jet engine to full speed. Thus, in theevent of an emergency such as overshooting the airfield, s'uflicientthrust is available to enable the aircraft to climb for a furtherattempt. By using the thrust reversing device described herein, theaircraft may be decelerated more rapidly with the engine revolutions ata high level, so that a relatively high engine speed is actuallybeneficial for landing. In the event of an emergency, the diverter coneis quickly returned to the aft position, thus allowing the full thrustof the engine to be immediately available.

While the device is operative as drawn and described, it should beunderstood that the arrangement is illustrative only, the specificstructural details being determined by development to suit particulartypes of engines and aircraft. Further, although the device has beenshown installed in the rear fuselage of a fighter type aircraft, theinvention is equally suitable for engines in nacelle type installations.-It is also noteworthy that the number and relative size of the openings22 may be varied considerably without departure from the spirit of thisinvention or. beyond the broad'teaching in this disclosure.

In recapitulation, the basic components of the thrust reversing deviceinclude an axiallymovable diverter cone which seals off the tail pipe ofthe jet engine, so that the exhaust gases are diverted through lateralopenings and between vanes which direct the gases forwardly andoutwardly from the aircraft. The general arrangement of these essentialcomponents is illustrated in Fig. 2.

The operation of this invention will be clearly comprehended from aconsideration of the foregoing description of the mechanical detailsthereof, taken in connection with the drawing and the above recitedobjects. -It will be obvious that all said objects are amply achieved bythis invention.

Further description would appear to be unnecessary.

We claim:

1. In combination, a jet engine having a tail pipe comprising an outercone, a concentric inner cone and an extension pipe continuing from saidouter cone, and a thrust reversing device comprising a diverter coneaxially slidable in said tail pipe, said outer cone having lateralopenings, a plurality of vanesin each of said openings,

said diverter cone seating on said inner cone when in the forwardposition and effectively blocking said tail pipe, so that exhaust gasesare directed through said openings, and said diverter cone covering saidopenings when in the aft position, said vanes being shaped to direct thegases forwardly therefrom, and hinged doors selectively covering saidopenings.

2. In combination, a jet engine having a tail pipe comprising an outercone, a concentric inner cone and an extension pipe continuing from saidouter cone, and a thrust reversing device comprising a diverter coneaxially slidable in said tail pipe, remote control means for movingsaiddiverter cone selectively forward and aft, said outer cone havinglateral openings, a plurality of vanes in each of said openings, saiddiverter cone seating on said inner cone when in the forward positionand efiectively blocking said tail pipe, so that exhaust gases aredirected through said openings, and said diverter cone covering saidopeningswhen in the aft position, said vanes being shaped to direct thegases forwardly therefrom, and hinged doors selectively covering saidopenings.

3. in combination, a jet engine having a tail pipe comprising an outercone, a concentric inner core and an extension pipecontinuing from saidouter cone, and a thrust reversing device comprising a diverter coneaxially slidable in said tail pipe, remote control means for moving saiddiverter cone selectively forward and aft, said outer cone havinglateral openings, a plurality of vanes in each of said openings, saiddiverter cone seating on said inner cone when in the forward positionand effectively blocking said tail pipe, so that exhaust gases aredirected through said openings, and said diverter cone covering saidopenings when in the aft position, said vanes being shaped to direct thegases forwardly therefrom, hinged doors selectively covering saidopenings, and means for opening said doors when said diverter cone is inthe forward position.

4. In combination, a jet engine installed in an aircraft, said jetengine having a tail pipe comprising an outer cone, a concentric innercone and an extension pipe continuing from said outer cone, a turbineexhausting between said inner and outer cones, and a thrust reversingdevice comprising a diverter cone axially slidable in said tailpipe,pilot controlled actuating means for moving said diverter coneselectively forward and aft, opposed openings in said outer cone andcorresponding outlets in the surrounding structure of the aircraft, aplurality of vanes in each of said openings, said diverter cone having atapered throat portion and a tail portion, said throat portion beingsubstantially flush with said outer cone and covering said openings whenin the aft position, said throat portion seating on said inner cone andsaid tail portion effectively blocking said tail pipe when in theforward position, so that exhaust gases are directed through saidopenings, said vanes being shaped to direct the gases forwardly throughsaid outlets, hinged doors covering said outlets and means for openingsaid doors simultaneously when said diverter cone is moved to theforward position.

Lindhagen et a1 June 6, 1950 Robson et al May 5, 1953

